Their study actually surveys THREE species of brooding brittle stars!
What does this mean? In MOST echinoderms, following fertilization juveniles pretty much settle out on their own and are left to grow/rear out on their own. But in some unusual instances there is actually parental care!
So, yes, some adult echinoderms rear juveniles! Yes! Baby echinoderms! I've detailed this behavior in starfish in some detail here. and of course, who can forget the life and death struggle of tiny asterinid starfish hermaphrodites who attack and eat one another in the "womb" of the mother?? (here)
Jannes' study focuses primarily on three brooding species in the South African area, including Amphiura capensis, Amphipholis squamata (both in the Amphiuridae) and one called Ophioderma wahlbergii
Jannes' work was actually surveyed here in GigaScience's own blog Jannes and co authors use three dimensional visualization tools, including x-ray micro tomography scans to unobtrusively visualize brooding juveniles without destructively sampling the original specimen. Neato!
This gives you an idea of what Amphiura capensis looks like..
|Image borrowed from Eastern Cape SCUBA diving! Go check em' out!|